Warehouse type home improvement and builders supply stores use order picker lift trucks to move bulky merchandise between storage, point of display and customer loading. The hereinbefore identified loading platform assembly is a lift truck attachment designed to quickly and safely provide transport for wide entryway or patio door modules and large crates or appliances. When moving large boxes or crates onto or off of the roller conveyor, the workman must stand at one side of or at the end of the roller conveyor and these positions are awkward and not the most effective for applying force to move the merchandise on to or off of the roller conveyor. Since the roller braking mechanism is released during loading and unloading, it would be dangerous to stand on the roller conveyor during loading or unloading operations in attempting to gain a force applying advantage relative to the conveyed merchandise.